Health Service Modelling Associates Programme
PenCHORD (the Peninsula Collaboration for Health Operational Research and Data Science) is one of the teams of PenARC.
PenCHORD began in 2010, and has worked with hundreds of local and national partners to use modelling and data science approaches to improve the operational delivery of health and social care services.
Our work is
The Health Service Modelling Associates is a 15 month data science and operational research training and mentoring programme.
Supported by the NIHR PenARC and the NHS Digital Academy, the full programme is provided free of charge to people working in health, social care and policing and is accredited by AphA.
hsma-programme.github.io/hsma_site/ - Visit Our Website for Free Training
Your emergency department is struggling.
You could try a range of different things…
Which of these is the right answer?
Healthcare tends to be full of queueing problems like this one.
Healthcare systems are full of resources
These resources experience demand from entities.
These entities might be
As these entities move through a pathway - a series of steps where these resources are used - queues can build up where there isn’t enough resource.
And these pathways are often very complicated!
There are lots of moving parts, and lots of variation.
Variation in when, and how frequently, people arrive
Variation in how long an activity in the pathway takes
Variation in the pathways people take within a single system
Making changes to pathways can be
And even if you do fix the original problem you were trying to solve, there’s a risk of knock-on effects elsewhere in the pathway that you didn’t foresee.
And even if you avoid that….
A system that is coping now might not cope
On HSMA, we teach a couple of different computer simulation techniques.
High-level technique that’s often suited to uncovering fundamental issues with pathway or wider healthcare system design
Individual-level modelling that is particularly interested in the impact of individuals’ decisions and interactions
Modelling focussing on the flow of entities through a pathway and use of resources, allowing detailed investigation of capacity, queues and waits
What we generally want to tackle our pathway problems in healthcare is Discrete Event Simulation (DES)
In a DES…
DES is so powerful because it gives us an in-silico (computer-based) reproduction of our pathway to play around with.
We can make any change we want
(e.g. more resources, higher demand, new pathway design)
safely and for free and see what impact it has on any metric we care to measure:
And so on!
That randomness and variation in our healthcare systems that we mentioned before? DES can cope really well with that!
Let’s imagine that people turn up to our system, on average, every 10 minutes.
However, sometimes no-one turns up for half an hour, and other times 3 people turn up simultaneously.
By using distributions we can produce random times that mimic real-world patterns.
Taking it even further, we can harness that variation for making the most of our models.
We can hold the random patterns consistent and change resource levels or pathway design
We can hold resources or pathway design consistent and allow randomness
This allows us to be sure the changes we’re testing really are responsible for the differences
This allows us to test our system in multiple parallel universes, running it tens or even hundreds of times!
Your DES won’t be a perfect one-to-one reproduction of the pathway you are modelling.
We have to make certain assumptions and simplifications, and we can’t capture every complexity.
However…
All models are wrong, but some are useful
• George E. P. Box
In this PenCHORD project, a DES model of the bladder cancer pathway at Royal Cornwall Hospitals Trust (RCHT) exposed two key system bottlenecks.
The model was used to support an on-the-spot rewrite of the pathway, resulting in multi-week reductions to waiting times.
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This HSMA project looked at the design of a COVID-19 vaccination clinic in North Devon, exploring
The model identified potential issues with the original proposed plans, and was used to refine the plans to enable a safe but efficient delivery of the vaccination programme.
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This HSMA project looked at ways to improve Urgent Treatment Care (UTC) performance. The team wanted to know
The model identified a need for additional rooms and the ED was redesigned as a result.
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This PenCHORD project created a simulation model of a mental health assessment pathway.
The trust in question was piloting an approach that would allow patients to book their appointments themselves.
The model was used to help
This HSMA project created a model of a paediatric neurodevelopmental (ADHD + autism) pathway. Waits had increased to a 2 years on average.
The team wanted to understand
The model showed that recruiting an extra lead clinician would not address the bottleneck - but an additional second assessor would.
You can find details about all of our previous and current Discrete Event Simulation projects on the HSMA website